1. Field of the Invention
The present invention relates to a technique of ejecting a liquid to a liquid ejection object while scanning at least one of a liquid ejection head and the liquid ejection object.
2. Description of the Related Art
Printing devices have widely been used as an output device of images generated by computers and images taken with digital cameras. The printing device creates ink dots during scans on a printing medium to complete a printed image on the printing medium. The printing device generally creates dots and prints an image on the printing medium, while scanning at least one of a print head and the printing medium. In the line printer designed to complete a printed image by one scan, degradation of the printed image is ascribed to a meandering scan. A technique has been proposed to control the meandering of a paper feed scan (scan of the printing medium) and thereby prevent such image degradation (see, for example, Japanese Patent Laid-Open No. H08-217302).
There has, however, been no specific consideration about dot creation control with a view to preventing such image degradation. The inventors of the present application have found image degradation due to a meandering scan not only in the line printer but in the serial printer designed to complete a printed image by multiple scans. Such image degradation is not restrictive in printing devices but is commonly found in various liquid ejection devices as the problem of uneven liquid ejection.